The impossibility of FTL information

In summary, Eberhard's theorem, Special Relativity, and Shanon's information theory are the only links in the chain that allow information to be transmitted over a classical channel. If relativity were to be falsified, there would be no other independent reasons to believe the speed of light is the maximum speed of information.
  • #1
Duplex
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I want to make an index over all things against FTL transmission of classical information. All theories, hypotheses, theorems, axioms and rules... you name it.

I'm not looking for explanations or references, only the headlines such as Eberhard's theorem, Special Relativity, and Shanon's information theory.

Of course you can say that it is sufficient to know that to extract the encoded information in entanglement, you need a classical channel to access the correlation between Alice's and Bob's measurements. That's one broken link in the chain, but I want to know all the other links.

I'm not a physicist, but I want to increase my knowledge of quantum mechanics to test the "hidden" hypothesis in my signature.
 
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  • #3
Relativity is the only reason we believe information can propagate no faster than light. Anything else is just a statement that this or that theory is consistent with relativity. For instance, you can't derive an upper bound to information's speed of propagation in quantum mechanics. However, you can show, as you noted, that entanglement doesn't allow the transmission of quantum information without exchanging signals (which, as we know from SR, can only propagate at or slower than the speed of light) and so quantum mechanics is consistent with relativity. If relativity were falsified, there would be no other independent reasons to believe the speed of light is the maximum speed of information. Of course, relativity theory is the foundation for all of modern physics and one of the most well-established experimental facts in scientific history—so when I say it's the "only" reason for disbelieving FTL communication, that is rather understating the situation a little.
 
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  • #4
It should be noted that Maxwell's laws of electromagnetism predict a VERY specific velocity for electromagnetic radiation (light). More specifically the "speed of light" is really the "speed of massless particles". To my knowledge (and please correct me if I am wrong - anyone), ALL massless particles travel at 'c'.
 
  • #5
snatchingthepi said:
To my knowledge (and please correct me if I am wrong - anyone), ALL massless particles travel at 'c'.

You're correct.
 

Related to The impossibility of FTL information

1. What is FTL information?

FTL (faster-than-light) information refers to any form of information that travels faster than the speed of light, which is considered the maximum speed in the universe according to the laws of physics.

2. Why is FTL information impossible?

According to Einstein's theory of relativity, the speed of light is the ultimate speed limit in the universe. This means that nothing, including information, can travel faster than the speed of light. Therefore, FTL information is deemed impossible.

3. Can anything travel faster than the speed of light?

No, according to our current understanding of physics, nothing can travel faster than the speed of light. There have been some theories and experiments that suggest the possibility of particles traveling faster than light, but none have been proven to be true.

4. What would happen if FTL information was possible?

If FTL information was possible, it would violate the laws of causality, which state that cause must precede effect. This means that effects cannot occur before their causes, and FTL information would lead to paradoxes and contradictions in our understanding of the universe.

5. Is there any way to achieve FTL information?

Currently, there is no known way to achieve FTL information without breaking the laws of physics. Some scientists have proposed theories such as wormholes and warp drives, but these are purely hypothetical and have not been proven to be possible or practical.

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